In an AC surface discharge type panel that is typical as a plasma display panel (in the following, abbreviated as a “panel”), a large number of discharge cells are formed between a front substrate and a rear substrate arranged facing each other. In the front substrate, a plurality of display electrode pairs each consisting of one pair of a scan electrode and a sustain electrode are formed in parallel to each other on a front surface glass substrate, and a dielectric layer and a protective layer are formed to cover these display electrode pairs. In the rear substrate, a plurality of parallel data electrodes are formed on a back surface glass substrate, a dielectric layer is formed to cover these, and on top of it, a plurality of barrier ribs are formed in parallel to the data electrodes, and a phosphor layer is formed on the surface of the dielectric layer and a side surface of the barrier rib. The front substrate and the rear substrate are arranged facing each other so that the display electrode pair and the data electrode stereoscopically intersect, are sealed, and a discharge gas containing 5% of xenon at a partial pressure ratio, for example, is sealed in a discharge space in the inside. Here, a discharge cell is formed in a part where the display electrode pair and the data electrode are facing each other. In a panel with such configuration, color display is performed by generating an ultraviolet ray by gas discharge in each discharge cell and exciting a phosphor each having a color of red (R), green (G), and blue (B) to emit light.
A subfield method, that is, a method of dividing one field period into a plurality of subfields and then performing display gradation by a combination of the subfields to emit light, is a general method of driving the panel. Each subfield has an initializing period, an address period, and a sustain period, generates an initializing discharge in the initializing period, and forms wall charges that are necessary for the subsequent writing operation on each electrode. In the address period, address discharges are generated selectively in a discharge cell that performs a display, and the wall charges are formed. Then, in the sustain period, a sustain pulse is applied alternately on the display electrode pair consisting of the scan electrode and the sustain electrode, a sustain discharge in the discharge cell where the address discharge was generated is generated, and image display is performed by making the phosphor layer of the corresponding discharge cell emit light.
Further, also in the subfield method, a drive method is disclosed in which the contrast ratio is improved by decreasing emission that does not relate to the display gradation as much as possible by performing the initializing discharge using a voltage waveform that changes gradually and further performing the initializing discharge selectively to the discharge cell where the sustain discharge is performed.
Specifically, the operation of initializing all cells is performed in which all discharge cells are discharged in the initializing period of one subfield among a plurality of subfields, and a selected initializing operation is performed in which only a discharge cell in which the sustain discharge is performed is initialized in the initializing period of other subfields. As a result, emission that is not related to a display becomes only emission accompanied by the discharge of the all cell initializing operation, and image display with high contrast becomes possible (for example, refer to Patent Document 1).
By driving in such way, luminance in the black display region that changes depending on emission that is not related to the display of an image becomes only faint emission in the all cell initializing operation, and image display with high contrast becomes possible.
However, in recent years, a panel has been made into a larger screen to achieve high definition, and because of that, the address discharge becomes unstable, the wiring discharge is not generated in the discharge cell where the display is supposed to be performed, and the quality of the image display is deteriorated, or the voltage that is necessary to generate the address discharge stably becomes high.
Patent Document 1: Unexamined Japanese Patent Publication No. 2000-242224